title: In vitro identification of cytochrome P450 enzymes responsible for drug metabolism.
abstract: Metabolism catalyzed by the cytochrome P450 enzymes (CYPs) represents the most important pathway for drug metabolism and elimination in humans. Identification of the CYPs responsible for metabolism of existing and novel drugs is critical for the prediction of adverse reactions caused by drug-drug interactions or individual genetic polymorphism. An integrated approach is described for CYP-mediated metabolic reaction phenotyping using both recombinant enzymes and human liver microsomes in combination of selective inhibitors or inhibitory antibodies. The in vitro method described includes screening of recombinant CYPs for metabolic activity, chemical inhibition or antibody neutralization, and correlation analysis with isoform-selective marker activities. The primary focus is on identification of the most common enzymes including CYP1A2, 2C9, 2C19, 2D6, and 3A4, although the same strategy could potentially be used for identification of other isoforms.
authors.affiliation: CREATe, Janssen Pharmaceutical Companies of Johnson & Johnson, Spring House, PA, USA.
authors.forename: Zhengyin
authors.initials: Z
authors.lastname: Yan
authors.forename: Gary W
authors.initials: GW
authors.lastname: Caldwell
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics*; D019388:Cytochrome P-450 CYP1A2 / Q000235:genetics*; D065731:Cytochrome P-450 CYP2C19; D065729:Cytochrome P-450 CYP2C9; D019389:Cytochrome P-450 CYP2D6 / Q000235:genetics*; D051544:Cytochrome P-450 CYP3A / Q000235:genetics*; D006801:Humans; D006900:Hydroxylation; D066298:In Vitro Techniques; D008658:Inactivation, Metabolic / Q000235:genetics; D008862:Microsomes, Liver / Q000201:enzymology; D020641:Polymorphism, Single Nucleotide
chemical_list: C450260:CYP2C9 protein, human; D065729:Cytochrome P-450 CYP2C9; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D019388:Cytochrome P-450 CYP1A2; D065731:Cytochrome P-450 CYP2C19; D019389:Cytochrome P-450 CYP2D6; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human